APPLICANT'S ABSTRACT: Few populations are beset with the constellation of economic, social and health problems that afflict homeless individuals. Alcoholism is one of their most common and serious problems. Given the nature and severity of their problems, the Institute of Medicine has suggested that the homeless need specialized substance abuse interventions. We propose to examine the efficacy of a novel treatment for chronically unemployed substance abusers, the Therapeutic Workplace, in homeless, alcohol-dependent adults. Prior research has shown that this intervention is effective in the treatment of heroin and cocaine dependence. The intervention integrates abstinence reinforcement contingencies of proven efficacy into a model supported work program. Patients are paid to perform data entry jobs in the Therapeutic Workplace. Those lacking needed skills are given intensive training. To reinforce abstinence from alcohol, patients can work and earn salary only when they remain abstinent from alcohol as assessed in weekday morning and random daily breath-alcohol tests. Patients are paid in vouchers instead of cash to reduce the chance they will use their earnings to Purchase alcohol or drugs. A randomized trial is planned over 5 years to evaluate the efficacy of this intervention and to assess the contribution of the abstinence reinforcement component in homeless, alcohol-dependent adults who complete an inpatient alcohol detoxification. After the detoxification, 156 participants will be invited to attend the workplace for 6 months and randomly assigned to one of three groups that will differ in the requirements for voucher reinforcement. One group will receive the full therapeutic workplace intervention in which vouchers are contingent on both abstinence and work. A second group will be paid for work, but will not have to provide an alcohol-free breath sample to gain access to the workplace (vouchers contingent on work only). A third group will receive vouchers on a noncontingent basis. This group will control for the increases in wealth associated with voucher reinforcement. Critical measures of alcohol use, other drug use, HIV risk behaviors, employment and housing will be assessed. We expect the most abstinence when both abstinence and work are required to earn vouchers. This study will allow for the rigorous evaluation of a novel approach to the treatment of alcohol dependence, the Therapeutic Workplace, in a group of homeless, alcohol-dependent individuals who desperately need effective interventions to control their alcohol use, and to improve their chronic conditions of unemployment and homelessness.